9,219 research outputs found
Innovation Preannouncement and Entry in a Vertically Differentiated Industry
When considering the preannouncement of the market introduction of a newly developed, durable good, an innovative firm faces a trade-off. By announcing early, the firm can prevent the loss of potential demand before the launch of its product. At the same time, the incumbent firm learns about the market introduction and has the opportunity to take preemptive actions against the innovative firm. This analysis shows under which industry conditions an innovative firm can be expected to preannounce its product launch into a vertically differentiated industry. Welfare considerations indicate that consumers would not necessarily be better off if the information about future product generations would be common knowledge and that there might even be situations in which they would prefer product preannouncements to be banned completely.
Dynamics and symmetries of a field partitioned by an accelerated frame
The canonical evolution and symmetry generators are exhibited for a
Klein-Gordon (K-G) system which has been partitioned by an accelerated
coordinate frame into a pair of subsystems. This partitioning of the K-G system
is conveyed to the canonical generators by the eigenfunction property of the
Minkowski Bessel (M-B) modes. In terms of the M-B degrees of freedom, which are
unitarily related to those of the Minkowski plane waves, a near complete
diagonalization of these generators can be realized.Comment: 14 pages, PlainTex. Related papers on accelerated frames available at
http://www.math.ohio-state.edu/~gerlac
Paired accelerated arames: The perfect interferometer with everywhere smooth wave amplitudes
Rindler's acceleration-induced partitioning of spacetime leads to a
nature-given interferometer. It accomodates quantum mechanical and wave
mechanical processes in spacetime which in (Euclidean) optics correspond to
wave processes in a ``Mach-Zehnder'' interferometer: amplitude splitting,
reflection, and interference. These processes are described in terms of
amplitudes which behave smoothly across the event horizons of all four Rindler
sectors. In this context there arises quite naturally a complete set of
orthonormal wave packet histories, one of whose key properties is their
"explosivity index". In the limit of low index values the wave packets trace
out fuzzy world lines. By contrast, in the asymptotic limit of high index
values, there are no world lines, not even fuzzy ones. Instead, the wave packet
histories are those of entities with non-trivial internal collapse and
explosion dynamics. Their details are described by the wave processes in the
above-mentioned Mach-Zehnder interferometer. Each one of them is a double slit
interference process. These wave processes are applied to elucidate the
amplification of waves in an accelerated inhomogeneous dielectric. Also
discussed are the properties and relationships among the transition amplitudes
of an accelerated finite-time detector.Comment: 38 pages, RevTex, 10 figures, 4 mathematical tutorials. Html version
of the figures and of related papers available at
http://www.math.ohio-state.edu/~gerlac
Quantum Mechanical Carrier of the Imprints of Gravitation
We exhibit a purely quantum mechanical carrier of the imprints of gravitation
by identifying for a relativistic system a property which (i) is independent of
its mass and (ii) expresses the Poincare invariance of spacetime in the absence
of gravitation. This carrier consists of the phase and amplitude correlations
of waves in oppositely accelerating frames. These correlations are expressed as
a Klein-Gordon-equation-determined vector field whose components are the
``Planckian power'' and the ``r.m.s. thermal fluctuation'' spectra. The
imprints themselves are deviations away from this vector field.Comment: 8 pages, RevTex. Html version of this and related papers on
accelerated frames available at http://www.math.ohio-state.edu/~gerlac
Coulomb field of an accelerated charge: physical and mathematical aspects
The Maxwell field equations relative to a uniformly accelerated frame, and
the variational principle from which they are obtained, are formulated in terms
of the technique of geometrical gauge invariant potentials. They refer to the
transverse magnetic (TM) and the transeverse electric (TE) modes. This gauge
invariant "2+2" decomposition is used to see how the Coulomb field of a charge,
static in an accelerated frame, has properties that suggest features of
electromagnetism which are different from those in an inertial frame. In
particular, (1) an illustrative calculation shows that the Larmor radiation
reaction equals the electrostatic attraction between the accelerated charge and
the charge induced on the surface whose history is the event horizon, and (2) a
spectral decomposition of the Coulomb potential in the accelerated frame
suggests the possibility that the distortive effects of this charge on the
Rindler vacuum are akin to those of a charge on a crystal lattice.Comment: 27 pages, PlainTex. Related papers available at
http://www.math.ohio-state.edu/~gerlac
Radiation from Violently Accelerated Bodies
A determination is made of the radiation emitted by a linearly uniformly
accelerated uncharged dipole transmitter. It is found that, first of all, the
radiation rate is given by the familiar Larmor formula, but it is augmented by
an amount which becomes dominant for sufficiently high acceleration. For an
accelerated dipole oscillator, the criterion is that the center of mass motion
become relativistic within one oscillation period. The augmented formula and
the measurements which it summarizes presuppose an expanding inertial
observation frame. A static inertial reference frame will not do. Secondly, it
is found that the radiation measured in the expanding inertial frame is
received with 100% fidelity. There is no blueshift or redshift due to the
accelerative motion of the transmitter. Finally, it is found that a pair of
coherently radiating oscillators accelerating (into opposite directions) in
their respective causally disjoint Rindler-coordinatized sectors produces an
interference pattern in the expanding inertial frame. Like the pattern of a
Young double slit interferometer, this Rindler interferometer pattern has a
fringe spacing which is inversely proportional to the proper separation and the
proper frequency of the accelerated sources. The interferometer, as well as the
augmented Larmor formula, provide a unifying perspective. It joins adjacent
Rindler-coordinatized neighborhoods into a single spacetime arena for
scattering and radiation from accelerated bodies.Comment: 29 pages, 1 figure, Revte
Labor Pooling in R&D Intensive Industries
We investigate firms’ incentives to locate in the same region to gain access to a large pool of skilled labor. Firms engage in risky R&D activities and thus create stochastic product and implied labor demand. Agglomeration in a cluster is more likely in situations where the innovation step is large and the probability for a firm to be the only innovator is high. When firms cluster, they tend to invest more and take more risk in R&D compared to spatially dispersed firms. Agglomeration is welfare maximizing, because expected labor productivity is higher and firms choose a more efficient, technically diversified portfolio of R&D projects at the industry level.
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